Sensitivity of triarylmethane light sensitive systems



United States Patent 3,486,898 SENSITIVITY 0F TRIARYLMETHANE LIGHTSENSITIVE SYSTEMS Eugene Wainer, Shaker Heights, Ohio, assignor toHorizons Research Incorporated, a corporation of Ohio No Drawing. FiledSept. 7, 1965, Ser. No. 485,535 Int. Cl. C09b 23/16; G03c 1/72, 5/24 US.Cl. 96-90 24 Claims ABSTRACT OF THE DISCLOSURE This invention relates toa non-silver photographic system sensitive to both ultraviolet andvisible light which may either printout directly, thus requiring nodevelopment, or which may produce a semi-latent image which maybedeveloped out by the application of infrared energy and which may befixed by heating or by a solvent rinse and which has sufficientphotographic speed to permit the use of a camera for the taking ofpictures in a photographic speed representing a significant improvementover the teachings of the prior art.

The persent photosystem achieves a greatly improved sensitivity overthat available from the teachings from US. Patent 3,102,810, by virtueof inclusion therein of a leuco base or a carbinol base of a simple,substituted, or pseudo-triarylmethane dye in which at least one of thearyls is fitted with specially selected substituents' which enhance theelectron withdrawing or electrophilic characteristics of this singlearyl group. I

United'StatesPatents 3,042,515; 3,042,516; 3,042,517;

3,042,518; 3,042,519; and 3,046,125 describe variously mixtures whichmay be designated slow photographically. In this group of materialsexposure times of a 275 Watt G.E. Sunlamp of the reflector type at adistance of requires 5 to 25 seconds of exposure before a density of 1in the colored image is produced.

United States Patent 3,102,810 describes compositions somewhat fasterphotographically speaking than those in the preceding patents. Whenexposed to a 275 watt G.E. Sunlamp of-the reflector type at a distanceof 10" compositions of U.S.- Patent 3,102,810 required periods of 5 to20 seconds to achieve a density'of 1. While images could be obtained atlesser exposures, down to'0.5 second, as described in the examples, thedensity of the'image thus obtained was very much less than 1.0 and inall cases no image was obtained under this light source at exposuretimes less than 0.5 second.

The compositions of the present invention yield densities of 1.0 forexposure times at least an order of magnitude less than those describedin US. Patent 3,102,810. For all of the systems to be describedhereinafter in this specification, exposure times of not more than 0.1second yield a density of 1.0 and in many cases this density is achievedfor exposure times as short as one hundredth of a second. Example 1 ofUS. Patent 3,102,810 reports that 30 seconds are required to give goodimages at F45 in bright sunlight, whereas Example 2 indicates that 6minutes at P45 in bright sunlight are required to produce a good image.The compositions to be described in the following specification yieldgood images at 1 second ex- Patented Dec. 30, 1969 ice posure at F45 inbright sunlight in a camera and in certain cases exposure times of asshort as 0.1 second yield the same density. Thus, the compositions of myinvention are, photographically speaking, a factor of 30 to 100 timesfaster than the non-silver photographic compositions described in US.Patent 3,102,810.

The panchromatic photosystem of this invention is characterized by anenhanced speed due to a synergistic effect obtained by the use of acombination of (1) color dye bases or secondary or tertiary aryl,heterocyclic, arylheterocyclic amines unsubstituted in a para positionon the ring structure, or with components having a reactive position forattachment of a methane carbon atom or mixtures of these in combinationwith (2) leuco bases 01' carbinol bases of triarylmethane dyes of bothsimple and substituted character in which at least one of the aryl orsubstituted aryl groups of the triarylmethane leuco bases is speciallytreated to increase strongly its electrophilic or electron withdrawingcharacteristics, in photosystems including organic halogen compoundswhich generate free radicals on exposure to radiation of a suitableWavelength. Preferably the photosystem also includes a suitable basematerial in which the light sensitive material and the combination ofsynergistically acting agents are dispersed or on which they may besupported in the form of a thin film or coating, which coating may ormay not contain a plastic binder.

In its simplest form the compositions of my invention may be describedas comprising the following:

(a) An organic halogen compound;

(b) A dye base, a conjugated dye intermediate or mixtures of the above,each of which may be characterized by the description secondary ortertiary aromatic amines containing a ring structure unsubstituted in apara position, or with other components having a reactive position forattachment of a methane carbon atom;

(0) One or more leuco bases or carbinol bases of a triarylmethanecompound having at least one aryl group specially substituted toincrease its electrophilic or electron withdrawing characteristics; and

(d) A carrier which supports (a), (b), and (0) either as a dispersion orsolution throughout the carrier or as an intimate admixture coated onthe surface of the carrier material in which said coating may or may notcontain a'plastic binder, and said carrier is a type which exhiibtslittle or no reactive hydrogen positions.

While useful results are available by disposition of the photosensitivesystem in or on carriers such as paper, coatedpaper, nitro-cellulose,cellulose acetate, polyvinyl acetate, ethyl cellulose, methyl cellulose,carboxy methyl cellulose, polystyrene, and the like, the preferredcarrier which yields the maximum photographic speed is one in whichpositions normally available for hydrogen replacement or abstraction isblocked by another substituent, preferably Cl. Carriers which arepreferred to the oxygen-containing bases such as the cellulosederivatives include polystyrene, polyvinylchloride, polyvinylidenechloride and copolymers of vinyl chloride and vinylidene respect tosensitivity and the development of color, it

appears that, either as a result of exposure to light or possibly simplyas the result of the mixture of the organic halogen containing compoundand the specialized leuco bases, a complex is formed which requires lessenergy to raise it to an excited state to permit the desired photolyticreaction to take place when such complexes do not form.

As in US. Patent 3,102,810, as the result of exposure to light of thesevarious systems with or without subsequent development by infraredenergy or heat, a sharp difference in solubility in certain solventsexists between unexposed and exposed areas. While this finding is ofexceptional importance in order to eliminate any residual color whichmay exist from the progenitor itself and which may mask the printouteffects, more important than the elimination of such color-maskingeffects is the fact that such differences in solubility may be utilizedfor fixing and stabilization of the printed image, even though in themajority of cases fixing by simple heating is possible.

Further, the capability for taking advantage of the difference insolubility is that as the result of solvent extraction, as defined inUS. Patent 3,102,810, hydrophilic-hydrophobic differentiation isavailable, depending on Whether or not the areas have been exposed tolight. The developed out dye image appears to be ionic in character, andexhibits hydrophilic properties, and tends to be insoluble in non-polarsolvents; whereas the unexposed progenitor Whether intermediate or dyebase form, even in the presence of the organic halogen containingcompound, is a covalent non-ionic compound, soluble in a variety oforganic solvents, and tends to be hydrophobic in character. Suchhydrophobic properties may be enhanced by placing the photosystem on ahydrophobic base, and as a consequence the system can be utilized as afoundation of photoetch processes and as a means for producing alithographic plate.

Another aspect of the present invention is in the provision of anon-silver photographic system which by a proper combination of (1)ultraviolet and/or visible light and (2) infrared may be used for theproduction of ofiice copy by a flexographic technique hereinafterdescribed.

Each of the components of this photosensitive system and the manner inwhich the photosensitive system is utilized will now be considered ingreater detail.

(A) ORGANIC HALOGEN COMPOUNDS CBr (carbon tetrabromide) HCBr (bromoform)C Br (hexabromoethane) C H Cr (am-benzotribromide) HC Br(pentabromoethane) C H COCBr (am-tribromoacetophenone) HCI (iodoform) CCl (hexachloroeth'ane) Cl CCONH (otaa-trichloracetamide) Each of theabove compounds yields a halogen free radical when the bond joining ahalogen atom to a polyhalogenated carbon atom is ruptured upon exposureto light. The presently preferred compounds for this invention arecarbon tetrabromide and etaa-tribromoaceto phenone, both of which can beprepared readily in their requ1s1te purity.

4 (B) THE DYE BASES, SECONDARY AND TERTI- ARY RING AMINES HAVING ANUNSUBSTI- TUTED PARA POSITION ON AN ARYL RING OR WITH OTHER SUBSTITUENTHAVING A RE- ACTIVE POSITION FOR ATTACHMENT OF A METHANE CARBON Thefirst of the several families of dye bases, dye progenitors orconjugated dye intermediates, which constitutes one of the synergists inthe present photosystem, comprises the styryl'dye bases and their highervinylene homologues, such as described in US. Patent 3,095,303, andwhose photographic action is described in US. Patent 3,102,810, in asynergistic system. The various types of the styryl dye bases includedin the above two aforementioned issued U.S. patents are included in thisdescription by reference.

The second of the several families of dye bases, or dye progenitors orconjugated dye intermediates which constitutes one of the synergists inthe present photosensitive system, comprises the cyanine dye bases suchas those described in US. Patent 3,100,703.

The cyanine dye bases included in US. Patents 3,- 100,703 and 3,102,810,:are included herein by reference and include substantially all of thosecorresponding to all of the different classes of cyanine dyes, includingsymmetrical and unsymmetrical monomethine cyanines, carbocyanines,dicarbocyanines, tricarbocyanines, hemicyanines, pyrrolocyanines andazacyanines.

A further class of bases useful in my photo process are those related tothe styryl dye bases and to the vinylene homologues described in US.Patent 3,102,810 and additionally containing nitrogen in the chain asset forth in column 7 of said patent.

A variety of dye intermediates may be utilized as substitutes for theabove dye bases and as one of the synergists for the purposes of myinvention. Typical compounds are listed in Table I and are primary,secondary or tertiary carbocyclic aryl amines containing anunsubstituted or open ring carbon para to the ring carbon to which theamine nitrogen is attached, i.e. compound which may be represented bythe following general formula Ar-ITI-A B wherein Ar represents acarbocyclic nucleus such as phenyl or naphthyl aryl and wherein Ar maybe unsubstituted or substituted provided that the ring carbon para tothe carbon to which the amine nitrogen is attached is not substitutedand A and B each represents H, lower alkyl (methyl, ethyl, etc.) oraryl.

In other words these amines may be represented by one of the followinggeneral formulas wherein A and B each represents H, alkyl, aryl oraralkyl and C represents substituents on the phenyl or naphthyl nucleusin any position other than that which the arrow points.

In addition to the heterocyclic compounds and/or dye bases described in.the above noted United States patents, particularly 3,102,810, a largenumber of other compounds are suitable for the present invention. TableII lists some representative compounds and is not intended to enumerateall of those which are suitable.

Of the compounds listed in'Table II, those preferred in the practice ofthe present invention are compounds in which the structure occurs in a 5or, 6 membered heterocyclic ring and the reactive hydrogen, i.e. thatwhich is most'easily replacable, is the hydrogen attached to the carbonindicated.

, TABLE 11 (The arrow marks the reactive position for attachment v foramethane carbon atom) (1) Benzofiavine base:

(3) Rosinduline:

(4) Indole:

(5) Carbazole:

(6) N-vinyl carbazole:

(7) B-carboline:

(8) Quinoline:

(9) Acridine:

(10) Phenanthridene v (3:4 benzoguinoline):

11 Quinoxa line (benzpyrazene):

. (12) Quinazoline 13 Phenoxazine: i F

7 (14) Phenothiazine (thiodiphenylamine) N SU 15) Carbazole indophenol:

( 16) Leuco carbazole indophenol:

(17) Carbazole thiazone:

(18) Carbazole oxazone:

(19) Indigo white:

(20) 2 indole 2' thionaphthene indigo white:

OH OH (21) 2,3'indo1e indigo white:

Ill H (22) 2 indole 2thionaphthene indigo white:

8 V (23) 4-[ 1-ethy1-2( 1H) -quin0lylidene) methyl] quinoline:

(24) 4 [2 methyl 3 (1 f ethyl v2(1H) quinolylidene)propenyl] quinoline:

C H C H5 (25) 4 [1 cyano 5 (3 methyl 2(3H) benzothia zolylidene)1,3-pentadienyl] quinoline (26) 4 [3 ethyl 2(3H)benzothiazolylidene)methyl] quinoline (28) 4-( 1-ethy1-2( 1H)-quinolyideneamino quinoline:

l R C 2H5 (29) 4 [(3 ethyl 2(3H) -benzoxazolylidene)2butenylidene1aminoquinoline:

30 4 [6 3 ethyl 2(3H) benzothiazolylidene)- 2,4 hexadienylidene]aminoquiholine:

7 (32) 4- (p-dimethylaminophenylazo quinoline:

(3 3) 4-p-dimethylaminostyrylquinoline:

(34) 4 [4 (p dimethylaminophenyl) 1,3-butadienyl] quinoline:

The substituted amines of Table I generally yield a deep color rangingfrom deep blue to deep violet. The simple heterocyclic bases of'Table IIgenerally yield a color ranging from green to blue. The indigo typebases generally yield a deep blue black or green black. A range ofcolors varying from red to blue can be obtained from the simpleheterocyclic bases by substituting the hydrogen most para to theposition of the arrow with a chromophoric group such as paradimethylamino phenyl azo. For example, in the case of quinoline such a compoundwould be 4-(p-dimethylamino phenyl azo)quinoline and the vinyl analoguewould be 4-p-dimethyl amino styryl quinoline. Such chromophoresubstitution yields the styryl bases describedearlier in thisspecification.

In the case of carbazole, the indophenol and the leuco indophenol areimportant intermediates. Thionation of the leuco indophenol thiosulfateof carbazole yields the thiazone. These various carbazole derivativescontaining chromophoric groups or groups which yield chromophores onoxidation are exemplified in Table II, as items 15 and 16.

Thus derivatives of the various heterocyclics may be utilized generallyfor preparation of dye bases for the purposes of my invention providingsuch dye bases have a position reactive with a methane type centralcarbon atom, or less preferably, an aryl ring having an open paraposition.

(C) LEUCO BASES OR CARBINOL BASES OF SIMPLE OR SUBSTITUTEDTRIARYLMETHANE DYES TREATED PARTICULARLY TO IMPROVE THE ELECTROPHILIC ORELECTRON WITH- DRAWING CHARACTERISTICS OF A SINGLE ARYL GROUP ON THECENTRAL CARBON ATOM Simple or substituted leuco or carbinol bases oftriarylmethane dyes are available from several classes. Class I has thegeneral formula given below: wherein R R R and'R are each selected fromthe group consisting of H, alkyl, arylakyl and aryl groups and they maybe the same or different and R represents a monovalent radical selectedfrom the group consisting of H, and OCH where X is H for the leuco baseand OH for the carbinol base, where A or B or both may be alphanaphthyl, beta naphthyl, o-anisyl, p-anisyl, p-biphenyl, p-alkylphenyl,p-chlorophenyl, phenyl, where A and B may be the same or different,where A and B may be combined together through an oxygen, a carbon,nitrogen, sulphur, selenium or tellurium bridge, where D is phenyl ornaphthyl. The phenyl radicals in the above compounds may be substitutedin the 2 and 6 positions taken with monovalent substituents from theclass Cl, Br, CN, OCH CH COOH, SO H, OH and other monovalentsubstituents of the same nature. Other A and B ring entities may also besubstituted in the 2 and 6 positions with monovalent substituents takenfrom the class Cl, Br, CN, OCH CH COOH, SO H, OH and other monovalentsubstituents of the same nature. Similar substituents may also bepresent in the 2 and 6 position on the D ring and the 3, 4 and 5positions on the D ring are preferably unsubstituted. In the case ofa-naphthyl, the naphthyl radicals may be substituted in the 2 and 8positions with monovalent substituents taken from the class Cl, Br, CH,OCH CH COOH, SO H, OH, where the substituents are the same or different,providing all are in the foregoing class.

When A and B are combined together a second class of triarylmethane dyessuitable for the purposes of my invention may possibly be described aspseudotriarylmethanes in which the combined A and B portions of thetriarylmethane generic formula given above are substituted with 3,6bisdimethyl or diethylamino anthracene, 3,6 bisdimethylamino xanthene,3,6 bisdimethyl or diethyl aminoseleno xanthene, 3,6 bisdimethyl ordiethylaminotelluroxanthene, 3,6 bisdimethylamino ordiethylaminotoluoxanthene, or 3,6 bisdimethylamino ordiethylaminoxanthene, p-pdimethylamino or diethylaminofluorene andmodifications thereof Where methyl or ethyl in the para position on theA and B portions of the ring struction may be substituted for itsopposite number of with hydrogen and where methyl, chloro, carboxyl,nitro, sulfonic and similar monovalent groups may be placed on orthopositions on the D ring structures, it being important, however, thatboth ortho positions on the or two prime or D ring be substituted asindicated with the same or both substituents, these positions beingproperly designated as the 2, 6 positions, and the 3, 4, 5 positionspreferably being unsubstituted; and where the pseudotriarylmethanessubstituted as described just above for the A and B portions may befurther substituted in the parapara prime positions with ring structuresas described previously for the general class of triarylmethanes; afurther class of pseudotriarylmethanes representing combined bridgestructures identified by the compound 5,9- dioxa-9,14-dihyrocoeranthyrylleuco base: chichibabins hydrocarbon: the benzoflavin nucleus as areplacement for the A and B substituents in accordance with thefollowing formula in which the para aminogroups may contain hydrogen,alkyl, aryl, or aralkyl groups in which these positive substituents maybe the same or different.

The foregoing description may be summarized by the generic descriptionof a triarylmethyl or pseudotriarylmethyl compound in which a centralcarbon atom exists exhibiting the triarylmethyl bonding and capable ofproducing the hydrol or the hydrogen leuco base.

One important aspect of my invention is the nature of.

the substitution on the D constituent which improves the electrophilicor electron withdrawing characteristics of the composition. Thisimprovement is developed invariably by substitution on the 2 and 6positions on the D ring with substituents which accentuate the electronwithdrawing characteristics of the entire ring. As indicated previously,the A and B rings may be phenyl or naphthyl and the substituents in the2 and 6 positions in the case of phenyl and 2 and 8 in the case ofnaphthyl which accentuate electron withdrawing characteristics may bechlorine, bromine, cyanogen, methyl, methoxy, carboxyl, sulfo, hydroxylor similar monovalent groups. The 3, 4 and 5 positions are preferablyleft unsubstituted.

The structures described above are illustrated Table III.

ll TABLE TIL-STRUCTURES ILLUSTRATING SUIT- ABLE TRIARYLMETHANE TYPE OFLUECO BASES 1) Generic formula, leuco malachite green type:

R R R R4=H, alkyl, arylalkyl or aryl X=H, OH, alkoxy, aroyl (ethers),halogen (C1 or Br),

or acetate (esters) A, B=phenyl, naphthyl, anisyl, biphenyl orsubstituted phenyl D phenyl or naphthyl Y'=Cl, Br, CN, OCH COOH, SO H,OH.

(2) Generic formula, closed ring type:

egy

(3) Generic formula, chichibabin type:

wherein A, B, D, R R R R X and Y have the same meanings as in (1) above.

12 (4) Generic formula, chichibabin closed ring type:

R1 R3 Z RZ A B Ri o Y Y \/X J A 1 N z 11 R4 wherein A, B, D, R,, R R R Xand Y have the same meanings as in (1) above wherein Z and AZB have thesame meanings as in (2) above.

(D) SPECTRAL SENSITIVITY The color sensitivity response or spectralsensitivity appears to bear a relationship to the color of thetriarylmethane free radical and does not appear to be affected by thecolor of the dye base or substituted amine. Table IV gives the color ofa number of triarylmethyl type radicals and the range of spectralsensitivity of the synergistic systems which are presumed to containsuch radicals as a consequence of the presence of carbon tetrabromideand exposure to light.

This table illustrates another important aspect of my invention, namely,the extension of the spectral range by increasing the size of the ringstructure attached to the central carbon atom.

TABLE IV.SPECTRAL SENSITIVITY DUE TO VARIOUS TRIARYLMETHYL COMPOUNDSSpectral sensitivity Radical (substituents on ring synergisticstructures omitted) Color of radical system, A.

(1) Triphenylmethyl Yellow 3, 500-5, 200 (2) Tri-o-anisylmethyl Orange3, 500-5, 400 (2131) 5,9-dioxa-9, 14-di-hydrocoeran- Red 3, 500-5, 600

r (4) D iphenyl-beta-napthyl methyl. WineBed. 3, 500-5, 700 (5)Diphenyl-alpha-napthyl methyl. Red-Brown 3, 500-6, 000 (6)Di-beta-napthyl phenyl methyl. Blue Red 3, 500-6, 800 (7) Chichibabinhydrocarbon Red Vio1et 3, 500-7, 000 (8) Tri-p-biphenylmethyl Deep Viole3, 500-7, 000 Blue-Green-Red 3, 500-7, 200

(9) Di-alpha-napthyl biphenyl methyl.

(E) PROPORTIO'NS The preferred proportions of active ingredients in mynovel photographic compositions are generally as follows: for each moleof the styryl or cyanine base, or open para position substituted aminesas listed in Table I or heterocyclic nitrogen compounds as listed inTable II, 5 to 20 moles of the leuco bases or carbinol bases asdescribed in Tables III and IV are used in combination with 50 to 300moles of the source of halogen free radicals such as carbontetrabrornide. A preferred composition comprises 1 mole of the dye base,substituted amine or heterocyclic nitrogen compound; 10 moles of thetriarylmethane compound; and 200 moles of the halogen free radicalsource.

If this active composition is to be coated onto a surface such as paper,or a clear or pigmented plastic substrate, the photochemically activecomposition is generally dissolved in a solvent such that 1 gram of thephotoactive composition may be dissolved in a volume varying from 2 to10 ccs. of such solvent. If a plastic binder is 13 utilized for filmforming characteristics an amount of such plastic binder is added to thesolvent volume just recited so as to yield solutions in said solventranging between 1 percent plastic binder based on the solvent up to 10percent.

(F) PREPARATION AND PHOTOGRAPHIC PROCESSING TECHNIQUE The photoactivecomposition, as described in the previous section, with or without thepresence of film formers is coated on a suitable substrate such aspaper, subbed paper, clear or pigmented plastic films, glass and thelike by dipping, spraying, roller coating, doctor blading or any of theusual techniques utilized by those skilled in the art of applyingphotosensitive coatings of uniform thickness. These photosensitivecompositions are mixed and applied in the dark and after application tothe desired surface are allowed to dry in the dark in a drying chamberfrom which air and oxygen has been removed by purging with nitrogen orcarbon dioxide. Drying is normally carried out at room temperatureutilizing flowing nitrogen or carbon dioxide to facilitate the drying.Slightly elevated temperatures may be utilized for drying purposes but,preferably, not exceeding 45 C.

The dried film is then exposed in an appropriate device to a suitablelight source such as daylight, ultraviolet lamps, floodlamps, orflashlamps and thereafter is developed for periods ranging between 30seconds and 2 minutes with an infrared source fitted with an appropriatefilter so that all visible and ultraviolet radiation below 7200 A. hasbeen removed. The most effective infrared developing band of wavelengthsis between 0.75 micron and 3 microns. A latent or semi-latent image isobtained on light exposure which develops out as a consequence of theinfrared treatment. Some fixing is achieved in this step and in thosesystems where the background color of the original dyed base orsecondary amine is not a disadvantage fixing may be completed by placingin an oven for 2 to 5 minutes at a temperature of 125 C. When thebackground color of the original starting materials is objectionablefixing may be accomplished after the infrared treatment by bathing in asolvent solution consisting of 3 parts of ethyl acetate and 17 parts ofbenzene (3:17) to remove the unreacted starting materials. Permanent andcomplete fixing results from such a procedure. The filter should cut offall radiation below 7 200 A. for compositions containing triphenyl leucocompounds but may have a cut off at 7500 A. when naphthyls and similararyl groups replace the phenyl groups in such compounds.

It is also possible to utilize the compositions of this invention in aflexographic process in which the compositions are positioned above asubject to be reproduced and then given a blanket exposure to visibleand/or UV. radiation after which they are subjected to infraredradiation alone.

(G) EXAMPLES Example 1 When 3 milligrams of the styryl base,4-p-dimethylaminostyrylquinoline, and 25 milligrams of the leuco base,4-4 bis (dimethylamino) 2"6" dichlorotriphenylmethane, were dissolved in10 ccs. of ethyl acetate containing 700 milligrams of carbontetrabromide, then coated on a clear or pigmented cellulose acetatesubstrate, excellent images were obtained on exposure in a camera for 1second at P45 in bright sunlight after infrared treatment with radiationin a wavelength range between 0.75 and 3.0 microns for 2 minutes. Theimage obtained was background clarified and fixed by bathing in asolvent solution consisting of 3 parts of ethyl acetate and 17 parts ofbenzene which removed the unreacted starting materials.

Example 2 3 milligrams of the styryl base,4-p-dimethylaminostyrylquinoline, and 25 milligrams of the leuco base,4,4

bis(dimethylamino) 2",6" dihydroxytriphenylmethane, are dissolved in 10ccs. of ethyl acetate containing 700 milligrams of carbon tetrabromideand coated on a clear cellulose acetate substrate. After drying, in anitrogen atmosphere the film was exposed in a camera at P45 in brightsunlight for 1 second and then infrared developed as described inExample 1 for 1 /2 minutes. An excellent image was obtained which wasfixed by bathing in solvent solution consisting of 3 parts of ethylacetate and 17 parts of benzene as in Example 1.

Example 3 3 milligrams of the azacyanine dye base, 2-(3-ethyl-2 3H)-benzothiazolylidine) -ethylidine aninobenzothiazole, and 25 milligramsof the leuco base, 4,4 bis(dimethylamino) 2",6 di-cyanotriphenylmethane,were dissolved in a solution of 700 milligrams of carbon tetrabromide in10 ccs. of a solution of 2 percent ethyl cellulose in toluene. Themixture was coated on white vinylite film in the darkroom and exposedunder a negative through a light from a photoflood lamp. A full exposedprint was obtained in 0.5 second of a neutral gray black color. A.similar mixture in which leuco crystal violet was substituted for thedicyanotriphenylmethane leuco base described above gave a barelyperceptible image after similar exposure and infrared developmentindicating at least a 20 times increase in speed when these speciallyprepared leuco bases were substituted for the prior art leuco crystalviolet.

Example 4 5 milligrams of 3-ethoxy-4'-methyldiphenylamine was mixed with40 milligrams of 4,4 bis(dimethylamino) 2",6"dicarboxyltriphenylmethane, in 10 ccs. of a 5 percent polystyrenesolution containing 500 milligrams of carbon tetrabromide. This mixturewas coated on baryta paper at a 1.5 mil wet thickness and allowed to dryin nitrogen. It was then exposed through a negative using the photofioodlamp utilized in Example 3 for 0.5 second. After infrared development,the sample was fixed by heating in an oven at C. for 3 minutes and animage of good density with clean background was achieved. When leucocrystal violet was substituted for the leuco base defined in thisexample, no image was visible after infrared development and the samplefogged completely on heating in the oven.

Example 5 4 milligrams of m-acetomidodiethylaniline was mixed with 30milligrams of 4,4 bis(diethylamino) 2",6 dimethyltriphenylmethane in 10ccs. of a 5 percent solution of polyvinylchloride in tetrahydrofurancontaining 700 milligrams of carbon tetrabromide and the mixture wascoated on subbed baryta paper and allowed to dry in the dark. It wasthereafter exposed to the photoflood lamp utilized in Example 3, for 1second through a negative yielding densities after infrared developmentand solvent leaching of 2.4 in the blacks.

Example 6 5 milligrams of N,N-dimethyl-m-toluidine and 35 milligrams of4,4 bis(dimethylamino) 2",6" disulfotriphenylmethane were dissolved in10 cos. of toluene containing 600 milligrams of carbon tetrabromide. Thesolution was coated on a clear cellulose acetate film and dried asdescribed previously. It was then exposed in a camera at P45 in brightsunlight and images of excellent quality were obtained after infrareddevelopment and fixing as described in Example 1 utilizing an exposuretime in the camera of 2 seconds.

Example 7 7 milligrams of p-ethoxyphenyl alpha naphthylamine and 40milligrams of 4-4' bis(dimethylaminophenyl) 2",6"dichlorotriphenylmethane were dissolved in 10 ccs. of the solutioncontaining 500 milligrams of carbon tetrabromide and 1 gram ofpolystyrene. This solution was coated on polyester subbed Mylar at a wetthickness of 2 mils and dried as before. Exposure to the photofiood lamputilized in Example 3 for 0.5 second produced images in the blacks afterinfrared development and thermal fixing of densities about 2.0.Substitution of leuco crystal violet for the triphenylmethane leucocompound described in this example yielded no image under the describedconditions and the sample fogged completely on thermal development.

Examples 8, 9, 10, 11 and 12 In five separate preparations, 4 milligramseach of N- vinylcarbazole, isorosinduline, indigo white, carbazolethiazone, and acridine (see Table II), and milligrams of the leuco basedescribed in Example 1 were dissolved in 10 ccs. of a 1 percent ethylcellulose solution comprising 4 ccs. of ethyl ether and 10 ccs. oftoluene which contained 800 milligrams of carbon tetrabromide. Thesewere spread on a clear cellulose acetate film, dried, exposed in acamera in bright sunlight at F45 for 2 seconds. After infrareddevelopment and solvent fixing as described in Example 1, excellentimages With densities in each case exceeding 1.0 in image areas wereobtained.

Example 13 3 milligrams of N-vinylcarbazole and 30 milligrams of 3,6bis(dimethylamino)-9-2,6 dichlorophenylxanthene were dissolved in 10ccs. of toluene containing 1 gram of polystyrene and 800 milligrams ofcarbon tetrabromide and spread in a wet thickness of 2 mils on barytapaper. Exposure followed by infrared development and solvent leaching asdefined in Example 1, the exposure being made to a flodlamp for 0.6second, yield an image exhibiting a density of 1.7 in 1 second.

Example 14 13 milligrams of 4-p-dimethylaminostyrylquinoline andmilligrams of 3,6 bis(dimethylamino)-9-2,6 chlorophenylthioxanthene weredissolved in 10 ccs. of ethyl acetate containing 700 milligrams ofcarbon tetrabromide and coated in a 2 mil wet thickness on a clearacetate base. After drying and exposure as defined in Example 1,infrared development and fixing an excellent image was obtained with anexposure time of 0.5 second in the camera exposure as utilized inExample 1.

Example 15 5 milligrams of 4-p-dimethylaminostyrylquinoline and 50milligrams of a leuco base in accordance with the generic formula givenas item 3, Table III, as the leuco base in which all of the Rs aremethyl groups, X=hydr0- gen, Y=Cl, and A, B and D are phenyl groups,Were dissolved in 15 ccs. of an equal part mixture of benzene and ethylacetate containing 1 gram of carbon tetrabromide. This was spread in a 2mil wet thickness on clear acetate in the dark as described before andafter drying a go d density image (density 0.7) was otbained in a cameraat F4.5 in bright sunlight at an exposure of 0.1 second, the image beingdeveloped out with infrared and solvent fixed as described in Example 1.

Example 16 The photosensitive composition described in Example 1(including the carbon tetrabromide) was dissolved in a mixture of 8 ccs.of ethyl acetate and 8 ccs. of benzene and coated in 1.5 mil wetthickness on polypropylene filled paper. After drying and exposure tothe photofiood lamp of Example 3 at a distance of 10" for 2 seconds, theinfrared developed image was fixed by extraction with benzene, thensponged with water containing 0.01 grams of aerosol OT per 100 ccs. ofwater and then washed with water. When placed on a lithographic press,good reproductions were obtained, the dye image areas being inkrepellent and the non-dye image areas being ink receptive.

1 6 Example 17 When 5 milligrams of the azacyanine base, 4-(1-ethyl-2(1H)-quinolylideneamino)quinoline, and 30 milligrams of the leuco base,4-4bis(dimethylamino) 2"6dichloro triphenylmethane, were dissolved in amixture of 8 ccs. of ethyl acetate and 2 ccs. of toluene containing 500milligrams of iodoform, then coated on a pigmented (TiO celluloseacetate substrate, excellent images were obtained on exposure in acamera for 0.5 seconde at P45 in bright sunlight after infraredtreatment with radiation and wavelength range between 0.75 and 3.0microns for 5 minutes. The image obtained was background clarified andfixed by bathing in a solvent solution consisting of 3 parts of ethylacetate and 17 parts of benzene which removed the unreacted startingmaterials. The color of the image was greenish-blue.

Example 18 3 milligrams of the azo base,4-(p-dimethylaminophenyl-azo)quinoline, and 45 milligrams of the leucobase, 4-4 bis(dimethylamino) 2"6" dichloro 4"methoxytriphenylmethane,were dissolved in 200 ccs. of a 50/50 mixture of ethyl acetate andbenzene containing 1000 milligrams of hexachlorethane, then coated on aclear cellulose acetate substrate, excellent images were obtained onexposure in a camera for 2 seconds at P45 in bright sunlight afterinfrared treatment with radiation in a wavelength range between 0.75 and3.0 microns for 5 minutes. The image obtained was background clarifiedand fixed by bathing in a solvent solution consisting of 3 parts ofethyl acetate and 17 parts of benzene which removed the unreactedstarting materials. The image was blue in color.

Example 19 When 5 milligrams of the dye base,4-[4-(p-dimethylaminophenyl)-1,3-butadieneyl]quinoline, and 30milligrams of a leuco base, 4-4'bis(dimethylaminonaphthyl) 26dichlorodiphenylmethane, were dissolved in 10 ccs. of a solution comprising 8ccs. of ethyl acetate and 2 ccs. of benzene containing 500 milligrams ofcarbon tetrabromide, then coated on a titanium dioxide pigmentedcellulose acetate substrate, excellent images were obtained on exposurein a camera for 1 second a P45 in bright sunlight. After infraredtreatment of radiation in a Wavelength range between 0.75 and 3.0microns for 7 minutes, the image otbained with background clarified andfixed by bathing in a solvent solution consisting of 3 parts of ethylacetate and 17 parts of benzene which removed the unreacted startingmaterials.

Examples 21, 22 and 23 Same as in Example 1 except that in place of the25 milligrams of the leuco base described in Example 1, the followingtriphenylmethyl compounds are used respectively.

(1)4-4bis(dimethylamino) 2"6" dichlorotriphenylmethylethylether (2)4-4bis(dimethylamino) 2"6" dichlorotriphenylmethylbromide (3)4-4bis(dimethylamino) 2"6" dichlorotriphenylmethacetate Example 24 Sameas in Example 1 except that composition included 50 mg. oftriphenylstibine (between 25 and mg. could be used.) Similar resultswere obtained.

Example 25 Same as Example 24 except that reflexographic technique wasutilized for exposure. Using clear cellulose acetate as the film thecoated film was laid on a subject to be duplicated, sensitive side ofthe film being up, and passed under a battery of illuminating andheating lamps, first being exposed to the illumination from a visibleplus U.V. source and then to I.R. lamps equipped with filters whichremoved all radiation to which the film might be sensi- Examples 26 and27 The process of Example 1 was repeated using 3 mg. of compounds havingthe formula:

in place of the 3 mg. styril base compound and in each instance apermanent black image was obtained.

I claim:

1. In a non-silver photosensitive composition comprising a mixture ofthe following:

(a) photolytically active organic halogen containing compoundsrepresented by the general formula A-C-X wherein A represents a memberof the group consisting of H, Cl, Br, I, alkyl, aryl and aroyl and eachXrepresents a halogen atom -selected from the group consisting of Cl, Brand I;

(b) at least one constituent selected from the group consisting of dyebases;

(c) at least one base selected from the group consisting of leuco basesand carbinol bases of triarylmethane compounds; and

(d) a carrier which supports the mixture of (a), (b) and theimprovements which comprise:

providing as constituent (b) a conjugated dye intermediate orheterocyclic compound having a reactive position for attachment of amethane carbon atom or a mixture thereof with a dye base; and

providing as constituent compounds having at least one aryl groupsubstituted to increase its electrophilic characteristics andrepresented by one of the following formulas: (l) generic formula, leucomalachite green type:

Y=Cl, Br, CN, 0on cooH, so,H, 0H.

18 (2) generic formula, closed ring type:

A, B, D, R1, R2, R3, R4, R5, X and Y have the same meaning as in (1)above Z=C (anthracene), O (xanthene), S (thioxanthene),

N (benzoflavine or acridine or merely a bond between A and B (fluorene)AZB=5,9, dioxa-9, 14 dihydroceranthryl.

1 (3) generic formula, chichibabin type:

/N N/ R: A \R| t X R1 A 0 R3 N/ R: \R4

wherein A, B, D, R R R R X and Y have the same meanings as in (1) above.(4) generic formula, chichibabin closed ring type:

wherein A, B, D, R R R R X and Y have the same meanings as in (1) abovewherein Z and AZB have the same meanings as in (2) above.

2. The composition of claim 1 wherein the ACX constituent is a compoundin which at least three bromine atoms are attached to a single carbonatom. 3. The composition of claim 1 wherein the AC-X constituent is CBrRI! RI wherein R and R each represents monovalent radicals selected fromthe group consisting of lower alkyl and benzyl; R" represents amonovalent radical selected from the group consisting of H and CN, d andn each represent a positive integer of from 1 to 2; m is a positiveinteger not greater than 4; and the sum of n-1 and m1 is not greaterthan 4; and Q represents the non-metallic atoms selected from the groupconsisting of C, O, S, Se, N, necessary to complete a heterocyclic ringwith not more than 6 atoms in the ring.

6. The composition of claim 1 wherein the constituent (b) is a cyaninedye base represented by the general formula )d1 b )n1=- (CH CH)el=Nwherein d and e each represents a positive integer of from of from 1 to2; n represents a positive integer of from 1 to 4; R represents anorganic radical selected from the group consisting of alkyl, aralkyl andaryl groups; R represents a member of the group consisting of hydrogenand cyano groups; and Z and Q each represents the nonmetallic atomsnecessary to complete a heterocyclic organic nucleus containing from 5to 6 carbon atoms in the ring, and a preferred R is 7. The compositionof claim 1 wherein the constituent (b) is a cyanine dye base representedby the general formula wherein d and e each represents a positiveinteger of from 1 to 2; n represents a positive integer of from 1 to 4;R represents an organic radical selected from the group consisting ofalkyl, aralkyl and aryl groups; R represents a member of the groupconsisting of hydrogen and cyano groups; each L represents a memberselected from the group consisting of CH and N, at least one L being anitrogen atom; and Q and Z each represents the nonmetallic atomsnecessary to complete a heterocyclic organic nucleus containing from 5to 6 carbon atoms in the ring, and a preferred R is 8. The compositionof claim 1 wherein the constituent (b) is a styryl dye base representedby the general formula wherein R and R' each represents monovalentradicals selected from the group consisting of lower alkyl and benzyl; arepresents a positive integer from 1 to 2; n represents a positiveinteger from 1 to 4; L represents a member selected from the groupconsisting of CH and N, at least one L being a nitrogen atom and Qrepresents the nonmetallic atoms selected from the group consisting ofC, O, S, Se, N, necessary to complete a heterocyclic ring with not morethan 6 atoms in the ring.

9. The composition of claim 1 wherein the constituent (b) is an aminerepresented by the general formula Ar-N wherein Ar represents phenyl ornaphthyl and each of E and F represents a member selected from the groupconsisting of H, alkyl, aryl, substituted alkyl and substituted aryl andthe carbon para to the ring carbon to which the N is attached is notsubstituted.

10. The composition of claim 1 in which the (a), (b), (c) mixture isdispersed in the support (d).

11. The composition of claim 1 in which the (a), (b), v(c) mixture issupported as a thin film on the support ((1).

12. The composition of claim 1 including a plastic binder for themixture.

13. The composition of claim 1 in which the support is a polymer of avinylidene halide selected from the group consisting of vinyl chlorideand vinylidene chloride and mixtures thereof.

14. The composition of claim 1 dispersed in a clear transparent solidfilm forming plastic.

15. The composition of claim 1 wherein the relative proportions of theseveral constituents are as follows: for each mole of (b) there arebetween 5 and 20 moles of (c) and 50 to 300 moles of (a).

16. The composition of claim 1 wherein the relative proportions of theseveral constituents are as follows: for each mole of (b) there areabout 10 moles of (c) and about 200 moles of (a).

17. A process for producing colored photographic prints which comprisespreparing the composition of claim 1; exposing the composition to acolored subject, thereby producing an image of said subject.

18. The process of claim 17 wherein the resulting image is intensifiedby heating for between 30 and seconds.

19. The process of claim 18 wherein the resulting print is treated witha solvent to wash away any undecomposed dye base, remaining afterexposure and heat intensification.

20. The composition of claim 1 wherein the triarylmethane compound is atriphenylmethyl compound.

21. The composition of claim 1 wherein the triarylmethane compound is atri-o-anisylmethyl compound.

22. The composition of claim 1 wherein the triarylmethane compound is5,9-dioxa-9,l4-dihydrocoeranthryl.

23. The composition of claim 1 wherein the triarylmethane compound isdiphenyl-beta-naphthyl methyl compound.

24. A process of producing colored photographic prints in which atransparent layer including the composition of claim 1 is disposedbetween a subject to be reproduced and source of visible and/orultraviolet radia tion, and while so positioned is exposed to suchradiation and thereafter to infrared radiation for a time suflicient todevelop a visible image of said subject.

References Cited UNITED STATES PATENTS 3,102,810 9/1963 Sprague et al.9633 OTHER REFERENCES Gould, Edwin: Mechanism and Structure in OrganicChemistry Holt, Rinehart & Winston, 1959, p. 208. QD 251 66.

Hine: Physical Organic Chemistry, McGraw Hill, 1962, p. 405. QD 476 H5.

NORMAN G. TORCHIN, Primary Examiner R. E. FIGHTER, Assistant ExaminerUS. Cl. X.R. 9648; 260240.1

